The present invention relates to collapsible containers, and particularly to bottom structures for collapsible containers made of paperboard. More particularly, the present invention relates to a relatively flat bottom structure for a rapid set-up, rectangle-shaped bulk box.
Bulk boxes are containers that are used to store bulk resins, food products, or other items. One problem with many bulk boxes is that it is necessary to fold the bottom flaps manually to create a box floor at the time the box is set up. Additional labor is needed to create a box floor at the time the box is set up. Manual floor set-up is a problem for rectangular and octagonal bulk boxes.
According to the present invention, a container includes a four-sided body and a floor positioned to lie in a bottom opening of the four-sided body upon movement of the four-sided body from a collapsed, flattened position to assume an expanded, opened position. The floor includes first and second floor sections.
The first floor section includes first and second bottom flaps coupled to the four-sided body along fold lines and a first connector. The first connector is coupled to the first and second bottom flaps and arranged to establish a first pivot axis therebetween so that the first bottom flap pivots automatically relative to the second bottom flap during container setup as the four-sided body is moved from its collapsed, flattened position to assume its expanded, opened position.
The second floor section includes third and fourth bottom flaps coupled to the four-sided body along fold lines and a second connector. The second connector is coupled to the third and fourth bottom flaps and arranged to establish a second pivot axis therebetween so that the fourth bottom flap pivots automatically relative to the third bottom flap during container setup as the four-sided body is moved from its collapsed, flattened position to assume its expanded, opened position.
In preferred embodiments, the four-sided body includes a set of four walls arranged consecutively in series to provide the four-sided body with a rectangular shape upon movement of the four-sided body to assume its expanded, opened position. A trapezoid-shaped first bottom flap is coupled to the first wall at a first fold line, a trapezoid-shaped second bottom flap is coupled to the second wall at a second fold line, a rectangle-shaped third bottom flap is coupled to the third wall at a third fold line, and a trapezoid-shaped fourth bottom flap is coupled to the fourth wall at a fourth fold line.
The first connector includes a first anchor plate glued or otherwise coupled to the second bottom flap and a first hinge coupled at one end to the first bottom flap and at the other end to the first anchor plate to establish the first pivot axis in the first floor section. The second connector includes a second anchor plate glued or otherwise coupled to the third bottom flap and a second hinge coupled at one end to the fourth bottom flap and at the other end to the second anchor plate to establish the second pivot axis in the second floor section.
Prior to setup, the four-sided body and the four bottom flaps cooperate to define a sleeve wherein the second and third walls and bottom flaps lie in one plane and the first and fourth walls and bottom flaps lie in a second plane along with the first and second connectors to establish the collapsed, flattened position of the four-sided body. When one force is applied to a fold edge provided between the first and second walls and an opposite force is applied to a fold edge provided between the third and fourth walls, the four walls are moved relative to one another from the collapsed, flattened position to assume the "rectangular" expanded, opened position. Simultaneously, the bottom flaps in the first and second floor sections pivot relative to one another and fold relative to the four walls to create a container floor automatically. The first bottom flap pivots relative to the second bottom flap about the first pivot axis and the fourth bottom flap pivots relative to the third bottom flap about the second pivot axis and the four flaps "intermesh" with one another to form a rectangular flat floor automatically during movement of the four-sided body to assume its expanded, opened position.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode Of carrying out the invention as presently perceived.